Quaternary ammonium salts of substituted propanolamines



United States Patent QUATERNARY AMlVIONIUM SALTS OF SUBSTITUTED PROPANOLAMINES Donald Wallace Adamson, London, England, assignor to Burroughs Wellcome & Co. (U. S. A.) Inc., Tuckahoe, N. Y., a corporation of New York N 0 Drawing. Application April 23, 1948, Serial No. 22,946

Claims priority, application Great Britain May 28, 1947 7. Claims. c1. zen-247.7

This invention relates to new therapeutic agents comprising a group of substituted gamma-hydroxypropylamines and has for its object the preparation or certain novel and useful quaternary ammonium slats of gamma, gamma-disubstituted-gamma-hydroxypropylamines. The new derivatives are therapeutically active as broncho dilators.

According to my invention I prepare N-trisubstitutedgamma, gamma disubstituted-gamma-hydroxypropylammonium salts of the general formula ethyl alcohol, dioxan at room temperature or at the 2,698,325 Patented Dec. 28, 1954 Example 2 3-dimethylamino-l l-diphenylpropanl-ol is prepared from the ethyl ester of fl-dimethylaminopropionic acid (29 grams) and the Grignard reagent made from bromobenzene (110 grams) and magnesium (17 grams) by a method essentially similar to that described in Example 1 (above) for the preparation of 3-N-piperidino-l:l-diphenylpropan l ol. 3 dimethylamino 1:1 diphenylpropan-1-ol has melting point 166 C. after recrystallisation from benzene or light petroleum.

3-dimethylamino-l:l-diphenylpropan-l-ol (4 grams) is dissolved in boiling ethyl alcohol (80 cubic centimetres) and ethyl iodide (5 grams) added and the mixture boiled under reflux for 2 hours. On cooling N-dimethyl-N- ethyl 3 hydroxy 3 :3-diphenylpropylammonium iodide crystallises out and melts at ZOO-201 C., with decomposition, after recrystallisation from ethyl alcohol.

Example 3 N-dimethyl-N-propyl-3-hydroxy-3 :3-diphenylpropylammonium bromide similarly is prepared by boiling 3-dimethyl-amino 1:1 diphenylpropan-l-ol with l-bromopropane in ethanolic solution for 5 hours (under reflux).

. The product melts with decomposition at 231-233 C.

boiling point of the solvent or at intermediate temperatures. Preferably an excess of the quaternising agent is employed. The solvent and the quantity used is preferably so selected that the quaternary salt crystallises from the reaction mixture on cooling; In cases when this cannot conveniently be done, a liquid in which the quaternary salt is insoluble (such as ether) is added gradually to the reaction product until crystallisation commences.

The N-disubstituted-'yy-disubstituted-'y-hydroxypropylamines may be prepared by bringing about a Grignard reaction between the appropriate fl-tertiaryaminopropionic acid alkyl ester and an appropriate organo-magnesium halide and subsequently hydrolysing the organomagnesium compound so produced, or alternatively they may be made by bringing about a Grignard reaction between the appropriate B-tertiaryaminoethyl aryl ketone and an appropriate organomagnesium halide, and subsequently hydrolysing the organomagnesium compound so produced.

The new quaternary salts to which this invention relates are crystalline compounds, soluble in water. They are useful as therapeutic agents having antispasmodic and broncho-dilating action.

The following examples illustrate the invention:

Example 1 A solution of the ethyl ester of B-piperidino-propionic acid (37 grams) in dry ether is added gradually to an ether solution of the Grignard reagent made from bromobenzene 110 cubic centimetres) and magnesium (17 grams), stirred and cooled in a bath kept at 0 C. After stirring in the cold for 1 hour, the reaction mixture is heated under reflux for 2 hours and is then cooled to 0 C. and stirred into crushed ice. Concentrated hydrochloric acid is then gradually added to the stirred mixture, cooled to 0 C., until acid to Congo red. After standing for 1 hour at 0 C. the salt which separates is filtered oit and washed with ether. The salt is suspended in chloroform and the suspension shaken with excess of concentrated ammonia solution and the chloroform layer separated, washed with water and dried. The chloroform Example 4 N dimethyl-N-butyl-3-hydroxy-3 3-diphenylpropylammonium bromide is prepared from 3-dimethylamino-1:1- diphenylpropan-l-ol and l-bromobutane in a similar manner to that described in Example 5. It has melting point 233-235 C. (with decomposition).

Example 5 Ethyl fi-di-n-propylaminopropionate (prepared as described by Weisel, Taylor, Mosher and Whitmore, Journal of the American Chemical Society, 1945, volume 67, page 1071) (40.2 grams) in anhydrous ether (50 cubic centimetres) treated with the Grignard reagent made from bromobenzene (110 grams) and magnesium (17 grams) under the conditions described in Example 1, yields 3- di-n-propylamino-l:l-diphenylpropan-l-ol which is purified by fractional distillation under reduced pressure (boiling point 153-154 C. at 0.1 mm.) and by recrystallization from light petroleum; the base has melting point 52.553.5 C.

The methiodide (N-methyl-N-dipropyl-3:3-diphenyl-3- hydroxypropylammonium iodide) prepared therefrom by the method described in Example 2 has melting point 181-183 C., after recrystallization from aqueous ethanol.

Example 7 Ethyl B-N-phenyl-N-methylaminopropionate (41.4 grams) in ether cubic centimetres), treated with the Grignard reagent prepared from bromobenzene grams) and magnesium (17 grams) in ether (200 cubic centimetres) in a similar manner to that described in Example 1, yields 3-N-phenyl-N-methylamino-1:1-diphenylpropan-l-ol, melting point"97 C. "(recrystallized from ethanol). The ethyl 'fi-N-phenyl-N-methylaminopropionate used as starting material is prepared by a methodessentially' similar to that described byEl derfield, Gensler, Barnbry, "Kremer, 'Brod'y, Hagem'an and Head, Journal of the American Chemical "Society, -19'46,volume 6?, page 1259, for the preparation of fl arylamihopropromcesters. I

Amixture of ethyl acrylate (4O -g.-),-methyl-aniline (42.8 grams) andacetic acid' (10grams) is boiled under reflux for '12-h'o'urs, cooled, andtaken-up in an equal volume of ether. The 'e'thereals'olution -is then washed withwater then with aqueous-sodium bicarbonat'e'sol'ution and finally with water. The "ethereal solution is then dried with anhydrous sodium sulphate, the ether evaporated, and the residual oil fractionally distilled untier reduced pressure. The required esteris collected at 98-100Cg/Os5mm. r I

3 N 'phenyl- N-methylamino-l il-diphenylpropan-l-ol (210 grams) is dissolved in ethanol (5-.0cc.),"m'ethy1 iodide (2.0 grams) added and the mixture allowedto stand for 24 hours. The N dimethyl-N-plrenyl-B:3-diphenyl-3 hytiroxypro ylammonium iodide which separatesmelts with decomposition at 176 C.,'after'recrystallization from aqueous ethanol.

Example 8 S-diethyIa'mino-I z'l-diphenylpropan --l ml is prepared fromtheethyl ester-of fl diethylaminopro'pionicacid 3 5 grams) and the'G'ri'gnard Ieagent=made frombromoben'zene(1'10 grams) and magnesium (-17'grarns) by -a method essentially similar to that described in-Ex'ainple '1 (above) for the preparation of 3-N-piperidino-1z1-diphenylpropan-l-ol. 3 diethylamino-l l-diphenylpropan- 1 01, purified by di'stillation underreduced. pressure (boiling'point 154 C./0. 2 m'm. o'r-by recrystallisation from light petroleum, has meltin'g'point 535 C.

3-diethylamino-1:l-diphenylpropan l-ol (1 gram) is dissolved in anhydrous acetone (2 cubic centimetres) methyl iodide (1 gram) in anhydrous acetone (2 cubic centimetres) added and the mixture allowed to stand for 2 hours. N-methyhN diethyl-3-hydroxy-3:3-diphenyl propylammoniumiodide, which crystallises out, is recryst a9ll9ise((l: frommethyl alcohol and'has melting'point 19 8- 1 Example'9 Ethyl B-N-pyrrolidinopropionate when treated with the Grignard reagent prepared from bromobenzene by {the same method as that described intExample 1 yields 3-N- pyrrolidino-l:l-diphenylpropan-l-ol, melting point 171- 172 C. (recrystallized from ethyl-acetate).

The ethyl fi-N.-pyrrolidinopropionate is prepared by mixing'pyrrolidine ('21 grams) with ethyl .acrylate :(30 grams) and allowing to :stand at-room temperature for several days. The ,product is distilled under reduced pressure, the required ester being collected at 108 110 C./23 mm.

3-N-pyrrolidino-1zl-diphenylpropan-l-ol (2.0 grams) is dissolved in chloroform (25 cubic centimetres), methyl iodide ('2.'0grams) added, and the'mixture allowed to stand'for 24-hours. Thecrystals offN-methyl-3z'3 diphenyl-3-hydroxypropylpyrrolidinium iodide which separate are recrystallised from methanol; .melting poi'nt 210 C.

Example Example 11 3-diallylamino-1:l-diphenylpropan .1 01 is prepared from ethyl 8-diallyl-aminopropionate.( 39 grams) and the Grignard reagent made from bromobenzene (110 grams) and magnesium (17 grams) by a method essentiallysimilar to that described in 'Example'l'for the preparation of 13 Diethylaminopropiophonone "hydrochloride (48.3 grams)r is added'in small. portions to the Grignardreagcnt prepared from cyclohexyl bromide (98 grams) and magnesium (14.6 grams) -in. 1.00 ether-stirred and cooled to 0 C. After boiling under reflux for 12 hours the produ'e't 'isWorked-up "by 'a similar metl od to that described .in Example 1. "3-diet-hylamino 1-cyclohexyl{1- phenylpropanl-ol zispurified by distillation under reduced pressure (boiiingjpoint 132-135 'C./0.02rnm3) and'by recrystallisation from light petroleum "(melting point S0i5 5'2 -CL-).

The tertiary base (1.0 ,gram) is dissolved in acetone (3 "cubic (centimetres) "and methyl iodide v(1 .0 grarn) added. 'After '-'stan'ding-'for'-several hours, crystallization of the product is completed-by gradual addition ofanhydrous ether. N methyl- N diethyl-3-cyclohexyl-3- phenyl-3-hydroxypropylammonium iodide has melting point -162" C. after recrystallisation from ethyl acetate and ethanol.

What I claim is: g V

11. Quaternarya moniumsalt's "of tertiary amino alcohols of'the'fo'rmula R1 wherein R1 and R2 are phenyl-and NB is'a member of the group Lconsi'sting of 1 lower "dialkylamino, piperidino arid-morpholi-no.

"2. Quaternary ammonium salts of tertiary amino alcoholsot the -'formula Uyelbhexyl OH GGH2CHZN=B "Ph'euyl wherein N -'B-is =a membertof the .group.consisting:of lower dialkylamino, morpholino, piperidino 'an'd ,pyrrolidino.

3. Quaternary ammonium salts of tertiary amino alcohol ofxthe .formula eyclohexyl 0411 f; 'ooH5cHzN=B phenyl where. N B' ispyrrOiidinQ.

4. Quaternary. ammonium salts of tertiary. amino alcoholsof theLfor-mula Where N=B is lower dialkylamino.

5. Quaternary ammonium salts of tertiary amino alcoholsof l tlre'formu-la cyclohexyl 'OH -C-'-GHzCH2N-=B "phenyl where N=B is piperidino.

6. Quaternary ammonium-salts of tertiary amino-alcohols of the formula cyclohexyl OH o cm0nm=e -.phenyl where N Bis' morpholino.

7. Quaternary ammonium salts of tertiary amino alcohols of the formula cyclohexyl OH C-CH2C HgN=B phenyl where N=B is diethylamino.

6 References Cited in the file of this patent UNITED STATES PATENTS OTHER REFERENCES Richter, Textbook of Organic Chemistry, pp. 230 and 10 240, (1938 edition).

Kleiderer et al., Report No. PE 981, Oflice of the Publication Board, Dept. of Commerce, Washington, D. C., pp. 38 and 39. 

2. QUATERNARY AMMONIUM SALTS OF TERTIARY AMINO ALCOHOLS OF THE FORMULA 